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MISSION HILLS MEDICAL GROUP, INC.
NPI 1225093305
Internal Medicine in Mission Viejo, CA

Active since April 20, 2006
25982 PALA, SUITE 250, MISSION VIEJO, CA 92691(949) 588-0051(949) 588-0052 Get Directions Write a Review

NPPES record last updated: August 22, 2020. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Mission Hills Medical Group, Inc. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

MISSION HILLS MEDICAL GROUP, INC. (NPI 1225093305) is a healthcare organization registered as an internal medicine in Mission Viejo, California and active in the NPI registry since April 2006. The organization lists Mon-ta Tsai, President, as its authorized official.

NPPES Registry Identity

NPI1225093305
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameMISSION HILLS MEDICAL GROUP, INC.
Location Address25982 PALA, SUITE 250Mission Viejo, CA 92691-6730
Mailing Address25982 Pala, Suite 250Mission Viejo, CA 92691-6730 · (949) 588-0051 · Fax (949) 588-0052
Phone(949) 588-0051
Fax(949) 588-0052
Organization SubpartNo
Authorized OfficialMon-ta TsaiPresident · (949) 588-0051
Enumeration DateApril 20, 2006
Last NPPES UpdateAugust 22, 2020
✔ NPI 1225093305 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
25982 PALA, Mission Viejo, CA 92691
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Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mission Hills Medical Group, Inc. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Clinicians Billing Medicare Through This Organization

2

Medicare enrollment records show 2 clinicians reassign Medicare billing to Mission Hills Medical Group, Inc., which bills Medicare for the services they deliver. Of these, 2 practice at this address. They are listed nearest first.

Clinicians, nearest first (2)

Helen Chang, MD
Internal Medicine
NPI 1639134687
25982 PALA SUITE 250
Mission Viejo, CA 92691
(949) 588-0051
✔ PECOSSame address
Mon Ta Tsai, M.D.
Internal Medicine
NPI 1427019231
25982 PALA SUITE 250
Mission Viejo, CA 92691
(949) 588-0051
✔ PECOSSame address

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Mission Hills Medical Group, Inc.'s NPI number?

The NPI number for Mission Hills Medical Group, Inc. is 1225093305. It was assigned to this organization in the NPPES registry on April 20, 2006.

Where is Mission Hills Medical Group, Inc. located?

Mission Hills Medical Group, Inc. is located at 25982 Pala Suite 250, Mission Viejo, CA 92691. The listed phone number is (949) 588-0051.

What is Mission Hills Medical Group, Inc.'s specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Mission Hills Medical Group, Inc. enrolled in Medicare?

Yes. Mission Hills Medical Group, Inc. is registered in the Medicare PECOS enrollment system.

How many clinicians bill Medicare through Mission Hills Medical Group, Inc.?

According to the CMS Revalidation Reassignment List (October 2026 release), 2 clinicians, all in Internal Medicine, reassign their Medicare billing to Mission Hills Medical Group, Inc.. A reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for the clinician's services. Of these, 2 practice at this address. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Mission Hills Medical Group, Inc. was last updated on August 22, 2020. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.